High
No Switched Live on Potterton Suprima HE

Your boiler has completely lost the electrical signal it needs to start running, meaning it is currently unable to provide any heating or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Internal fuse blown, no mains supply, or faulty control PCB/transformer.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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